Tom realized that he ________ his physicsbook at home when he reached school．

It’s said that Lucy’s mother took up a fruit-picking job for two years in a foreign county and it is awork.

It’s generally believed that the_________of the Dragon Boat Festival is to celebrate the great poet Qu Yuan.

His failure in the mid-term exam came as no surprise ________ the fact that he had not got himself well-prepared for it.

wild animals in the world _____ , sowe must take measures to protect them.